It's 11 p.m. on a Thursday night and a full moon shines down on two large buses crammed full of what might pass for exhausted tourists waiting outside a nondescript chain link fence. The cries of children and babies can be heard above the idling engines.

In a few minutes the gate opens and scores of newly arrived Syrian refugees — ranging from the very young to the very old — take tentative steps off the buses into the cold night air. Bundled in their arms are infants swaddled in thick blankets, jars of home-grown olives, plastic bags and suitcases jammed with clothing and other odds and ends.

This is their first stop in what will be an hours-long process to get registered by the Jordanian Armed Forces (JAF) and later by the United Nations High Commissioner for Refugees (UNHCR) at the Zaatari refugee camp a few miles down the road.

One especially frail and wizened woman grabs our attention. We learn her name is Zaela, that she is 94 years old and from Dara'a. Clutched in her tattooed hands is a small plastic bag with boxes of eye drops — one of the few possessions she managed to grab before fleeing to her village. "These are the belongings of my life," she says softly, her eyes filling with tears. "God gives and God takes. I have to be grateful for what I have."

My colleague Kari Diener and I have joined UNHCR's regional coordinator for Syrian refugees, Panos Moumtzis, on a late night visit to this, the Mafraq refugee registration center. We wanted to see firsthand the sea of humanity that is streaming over the Jordanian border now — day and night.

More than a million have fled Syria

The number of refugees is continuing to skyrocket. More than a million have fled Syria to countries across the region; in Jordan alone, JAF AND UNHCR are now registering between 2,500 and 4,000 newly-arrived refugees each day. And that doesn't include what officials guess is another 500-700 illegal crossings each day.

Initial UN estimates, just a couple of months ago, of 300,000 refugees in Jordan by June were quickly surpassed last month. Now the UN has doubled its estimate to 600,000 by the start of summer and, if the crisis continues, a million by year's end. That's one million Syrian refugees in a country of just over six million people.

Further complicating matters, the UN says its appeal for the Syria crisis is only 19% funded.

"The situation is unsustainable," says Andrew Harper, the senior UN official responsible for managing his agency's response to the crisis in Jordan. "We've never seen anything like this. Refugees are coming to a country with no natural resources — with no end in sight [to the war]."

To its enormous credit, the government of Jordan has no plans to shut down the border with Syria, but the implications for this water-strapped nation, experiencing its worst economic crisis since 1989, are enormous. Already the huge influx of refugees has pushed up the price of rent and food. Schools are operating double shifts to accommodate Syrian children. Competition for jobs is increasing. And tensions between locals and refugees are rising.

The Jordanian government requires that all refugees must first be brought to live in the Zaatari refugee camp which opened in July 2012, and if it hasn't already reached its capacity of 110,000 refugees (no one knows for sure how many are in Zaatari now), it will soon.

Because Jordanian citizens are allowed to sponsor as many refugees as they like, hundreds of thousands with the means to do so have since paid to move their families out of Zaatari into the capital of Amman or elsewhere in the country.

Lasting access to water is key

One of the most serious crises looming on the horizon for Jordan is the strain refugees are putting on host communities already struggling to cope with Jordan's limited water supply. In fact, even before tens of thousands of Syrian refugees began arriving last year, Jordan was known to be the fourth most water scarce country in the world. That's why a lot of Mercy Corps' work here is focused on alleviating some of these acute needs.

In Zaatari camp, for example, Mercy Corps has finished drilling two wells and constructing a state-of-the-art pump station and chlorination system capable of providing clean water to 65,500 refugees a day. The Mercy Corps team worked with hydro-geologists to assess the natural water supply below ground before drilling began so we could be sure the supply will be sustainable and continue to support local communities after this crisis is over.

We're also looking to address Jordan’s future water needs by renovating the municipal water systems of Mafraq and Ramtha to decrease leakages while increasing the supply of water by 25 percent for 400,000 people.

A plea to make voices heard

Back in the Mafraq registration center, a little over six miles from the border with Syria, the sound of bombs rumbles in the distance.

Traumatized children, some almost catatonic, gather around us as we talk with their weeping parents and grandparents. No one has the energy or desire to play at 1 a.m.

"I have only one request," pleaded a middle aged man who was afraid to tell us his name. He'd been on the run for six weeks with 19 members of his extended family after his home and neighborhood in the suburbs Dara’a came under attack by the Syrian military. "What took a lifetime to build stone by stone was gone in a minute," he said, speaking of his house. "Please make our voices heard to the world. Every day is worse than the day before."

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